Multi-isinstance idiom (Re: Deprecate tabs for indenting (was Re: Indenting with tabs vs spaces))

[Greg Ewing]

Bjorn Pettersen wrote:
> 
> > From: Courageous [mailto:jkraska at san.rr.com]
> >
> >     if isinstance(f, future.Step)          or \
> >        isinstance(f, future.Status)        or \
> >        isinstance(f, future.Announce)      or \
> >        isinstance(f, possibility.Observe)  or \
> >        isinstance(f, future.Incarnate)     or \
> >        isinstance(f, future.Start)         or \
> >        isinstance(f, future.Timeout):
> 
> Ack, so much typing :-)

How about

  class ClassesOfInterest(future.Step, future.Status, future.Announce,
    possibility.Observe, future.Incarnate, future.Start,
future.Timeout):
      pass

  if isinstance(f, ClassesOfInterest):
    ...

-- 
Greg Ewing, Computer Science Dept, University of Canterbury,	  
Christchurch, New Zealand
To get my email address, please visit my web page:	  
http://www.cosc.canterbury.ac.nz/~greg